I have been using my shell to travel through the Sands of Time and I ended up in another timeline where Rogues were able to learn a skill called Disguise, which allowed them to carefully disguise themselves as other humanoids.

With my -almost- unlimited power, I have brought to our timeline this spell and some characters that will teach you how to use it.

Disguise

Starting at level 2, all rogues will be able to talk to their trainers located in the starter zones to get a quest that will lead them to learn the new skill of Disguise.

They will need to learn all of the available disguises from other characters located all around Azeroth. But don't think it will be easy, after learning how to disguise as someone, they will need to gather the appropriate materials to do so.

These disguises are fragile, and any hostile action will reveal your identity.

Note: This skill is not custom (the way to obtain it, is), I have been doing a lot of research to bring back to life discarded / unused mechanics from early days of the game. More to come!

Will Taurens get their Plainsrunning ability? Paladins original Crusader Strike (debuff for holy spell damage, had an animation of a special attack like Seal of Command procc) and Schools of Magic usage skills too?? :D

I think it should serve a practical purpose. For instance, certain quests require you to collect items found in camps or groups of mobs. This makes certain quests fairly difficult to perform solo for rogues in contrast to other classes. Disguises could be used to give those quests an alternative route.